Each BS is in the center of own hexagonal cell and BSs operate beside each other.
We assume that the small scale fading of each channel follows Rayleigh fading with zero mean and unit variance.
For large scale fading, we use the log-distance pathloss model in [1]}.
The distance between adjacent BSs is \(2\ \rm km\) .
The minimum distance between BS and user is \(100\ \rm m\) .
Considering a \(2.4 \ \rm GHz\)  carrier frequency with \(10\ \rm MHz\)  bandwidth, we use \(8.7\ \rm dB\)  lognormal shadowing variance and \(5 \ \rm dB\)  noise figure.
For simplicity, we assume an equal target SINR for all users, i.e., \(\gamma _{i,u}=\gamma \)  for all \(i,u\) .
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